Community Profile

Bobby Fischer

Last seen: 8 månader ago Active since 2020

All

Content Feed

View by

Question

Surf command to plot simple surface
Hi what is happening here: close all x = -1 : 0.1 : 5; y = x; [X, Y] = meshgrid(x,y); Z = 2*X - X*Y + 2*Y; surf(X, Y, Z)...

ungefär ett år ago | 1 answer | 0

1

Question

Boundary value problem solvers in Matlab accept mixed boundary conditions, neumann boundary conditions?
Boundary value problem solvers in Matlab accept mixed boundary conditions, neumann boundary conditions?

ungefär ett år ago | 0 answers | 0

0

Question

simple fmincon problem, optimization toolbox
I have an optimization problem in that Matlab solves depending on the initial value given. First, I give X0 = [10 10 10] as the...

ungefär ett år ago | 1 answer | 0

1

Question

Show stats in bvp4c
Hi, I would like to see the stats, like the number of iterations. I have 'Stats' 'on' but doesn't show anything. Thanks for yo...

mer än ett år ago | 1 answer | 0

1

Question

bvp4c's guess for boundary conditions
Hi. I'd like to know why the initial guess for the solution shouldn't always be the boundary conditions themselves. That is, why...

mer än ett år ago | 1 answer | 0

1

Question

Light direction in surfl
Hi, I don't understand why it is not centered. x = -1:.1:1; y = -1:.1:1; [X,Y] = meshgrid(x,y); z = X.^2 + Y.^2; surfl(x,y...

mer än ett år ago | 1 answer | 0

1

Plot 2D data colormap
This could help: x = -3 + 6*rand(50,1); y = -3 + 6*rand(50,1); v = sin(x).^4 .* cos(y); F = scatteredInterpolant(x,y,v); ...

mer än ett år ago | 0

Question

Anomaly with comments and rating in one file in File Exchange.
https://www.mathworks.com/matlabcentral/fileexchange/85900-seawater-density-from-salinity-temperature-and-pressure I posted thi...

nästan 2 år ago | 1 answer | 0

1

Question

Function 'subs' different output for a (similar?) input
clc syms F(t) F(t)=[-5*cos(2*t) -5*sin(2*t) 3*exp(2*t); -2*(cos(2*t)+sin(2*t)) 2*(cos(2*t)-sin(2*t)) 0; cos(2*t) sin...

nästan 2 år ago | 1 answer | 0

1

Solved

Select every other element of a vector
Write a function which returns every other element of the vector passed in. That is, it returns the all odd-numbered elements, s...

nästan 2 år ago

Solved

Generate a vector like 1,2,2,3,3,3,4,4,4,4
Generate a vector like 1,2,2,3,3,3,4,4,4,4 So if n = 3, then return [1 2 2 3 3 3] And if n = 5, then return [1 2 2...

nästan 2 år ago

Solved

Make the vector [1 2 3 4 5 6 7 8 9 10]
In MATLAB, you create a vector by enclosing the elements in square brackets like so: x = [1 2 3 4] Commas are optional, s...

nästan 2 år ago

Submitted

Fourier series finite expansion.
I did this to learn grosso modo how Fourier series work.

nästan 2 år ago | 2 downloads |

Question

Matlab license expiration, now?
Now I get this message when I open Matlab: ---------------------------------------------------- Your MATLAB license will ...

nästan 2 år ago | 1 answer | 0

1

confusion on a new schema for solving ode
Hello, function euler1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clc clear tic delta_q=1e-4; q1=0;...

nästan 2 år ago | 0

| accepted

Solved

Finding Perfect Squares
Given a vector of numbers, return true if one of the numbers is a square of one of the other numbers. Otherwise return false. E...

nästan 2 år ago

Solved

Return area of square
Side of square=input=a Area=output=b

nästan 2 år ago

Solved

Maximum value in a matrix
Find the maximum value in the given matrix. For example, if A = [1 2 3; 4 7 8; 0 9 1]; then the answer is 9.

nästan 2 år ago

plot log with factor 20
Hello a=1.03; h=(a^200-a^20)/9; ypoints=a^(20):h:a^200; xpoints=log(ypoints)./log(a); figure(1) close(1) figure(1) h...

nästan 2 år ago | 1

| accepted

Question

Discrepancy with easy ODE.
Hello, don't know why the discrepancy. function fcno y0=linspace(0,2,20); t0=linspace(0,3,100); figure(1) close(1) figure...

nästan 2 år ago | 1 answer | 0

1

Solved

Find the sum of all the numbers of the input vector
Find the sum of all the numbers of the input vector x. Examples: Input x = [1 2 3 5] Output y is 11 Input x ...

nästan 2 år ago

Solved

Given a and b, return the sum a+b in c.

nästan 2 år ago

How to solve 'Index exceeds matrix dimensions.' error?
Hi, there was a bunch of things to correct. Don't know if the result still has some value because I don't know what I was workin...

nästan 2 år ago | 0

Question

ode45 fail with pendulum
Hello. I have proof that in my machine the pendulum goes all the way around, contradicting reality. Any thoughts? -------------...

nästan 2 år ago | 1 answer | 0

1

How can i plot surfaces for a recursive function?
Hi, I have written this code. Is this what you meant? function []=bobby_98(n) lon=20; x=linspace(-1,1,lon); y=x; z=zeros(l...

mer än 2 år ago | 0

Question

Start new session everytime
Hi, I would like Matlab to open with the command window and no editor tabs open. That is, if I had editor tabs open in my last...

mer än 2 år ago | 0 answers | 0

0

Question

Quadrature rectangles transparency in plot
Hi, How can I change the transparency of the rectangles? function [I]=bobby_85(n) % n=30; n=300; p=1; h=1/(n-1); I=0; x...

mer än 2 år ago | 0 answers | 0